In this article, power losses and total harmonic distortion performance of back-to-back converters built with 2-level topologies having different pulse width modulation schemes and 3-level topologies in a low power on-grid wind energy conversion system (WECS) have been investigated. SIMULINK/MATLAB simulation was run to calculate THD and also the determination of the switching instances of the active elements for loss calculation. A pulse by pulse calculation algorithm has been used for calculating steady state losses and switching losses. The power loss results for each topology and switching schemes have been compared. THD performances have also been compared and possible ways to decrease have also been discussed. Neutral point voltage balance of the 3-level topologies was also accomplished for more accurate and realistic results.

Keywords: 2-level topology, 3-level topology, Space vector modulation (SVM), Power loss of semiconductors, Total harmonic distortion (THD)